1. Field of the Invention
This invention relates to a jack extension tube for use on power seat adjuster mechanisms for vehicles and, in particular, to a jack extension tube having low-noise operational characteristics and a low-torque internal stop-release and which can be mounted to an existing link in the seat adjuster mechanism by a fastener such as a rivet.
2. Description of Related Art Jack extension tubes are used in power seat adjuster mechanisms for vehicles to operably connect a vehicle seat track or seat back to a powering mechanism to move the seat or any component thereof in a desired direction via a link member. By varying the length of the tube, jack extension tubes allow a particular seat adjuster mechanism to be used with seats on different vehicle models. Further, the tubular construction allows cost savings and weight savings over a solid machined rod. Two known prior art jack extension tubes are shown in greater detail in commonly-assigned U.S. Pat. Nos. 5,312,198 and 5,536,100 issued May 17, 1994 and July 16, 1996, respectively. Typically, the link member is mounted to the extension tube by a fastener such as a shoulder bolt with an attached nut, a pin, a rivet and the like.
However, because these extension tubes are often manufactured solely from steel or other metal components, some prior jack extension tubes have been known to make excessive amounts of noise during operation--more than is aesthetically pleasing while adjusting the seat in the passenger compartment of the vehicle. Further, prior extension tubes are often subject to "chucking"--looseness between components of the jack extension tube which contributes to unacceptable noise and vibration.